1. Field of the Invention
This invention relates to a lock core mechanism with alarm function, particularly to one having a lock core body provided with a core plate therein, a projecting rod, a core cover-plate, a housing, an electric circuit plate with buzzing function, a follower member and an actuating elastic assembly provided with an actuating member and a contact member, whereby the electric circuit plate will not be activated to sound for alarm only when a matching key is inserted in a keyhole of the lock core body to push the projection rod downwards to touch against an actuating piece of the electric circuit plate, and simultaneously turned to rotate the core plate to make the follower member roll over and press the elastic member downwards to touch against the contact member. Otherwise, the electric circuit plate will sound when a picking tool is inserted to push the projecting rod downwards to touch against the actuating piece without making the elastic member touch against the contact member, or when a special tool is inserted to forcedly rotate the follower member to roll over and press the elastic member downwards to touch against the contact member without making the projecting rod touch against the actuating piece.
2. Description of the Prior Art
Generally speaking, most known conventional locks simply use a key for locking and unlocking. At present, locks are designed to be provided with complicated structures for achieving the anti-theft purpose. However, no matter how complicated these known locks are constructed, such locks only can delay the time of being unlocked by thieves and has no way to stop such illegal unlocking of the thieves because the lock cores of such locks are still easily pried open by skilled thieves with special tools or mater keys in a short time, thus losing the anti-theft function.
The main purpose of the invention is to offer a lock core mechanism with alarm function by having a lock core body equipped with an alarm device therein and adapted to be assembled in any locks to sound for alarm when activated, thereby achieving the purpose of scaring away thieves so as to prevent anything from being stolen.
The main feature of the invention is to provide a lock core mechanism with alarm function mainly including:
a lock core body having a keyhole formed in one end thereof and a core plate disposed therein, the core plate capable of being rotated under a turning movement of a key and having a combining hole formed in a center thereof and an elongated hole formed proximate a circumferential edge thereof;
a projecting rod passing through the core plate of the lock core body and having a retaining portion disposed at an upper portion thereof and a spring located between the retaining portion of the projection rod and the core plate of the lock core body and allowing the projecting rod to move telescopically under a downward movement of the key;
a core cover-plate fitly covered in the lock core body and extended through by the projecting rod, the core cover-plate having a through hole and an aperture, the aperture provided to be extended through by the projecting rod;
a housing connected with the lock core body and having a supporting ridge disposed in an inner wall thereof;
an electric circuit plate fixedly attached to a bottom of the supporting ridge of the housing and having a through hole, an actuating piece corresponding in location to the projecting rod, and at least one alarm unit;
a follower member accommodated in the housing and having an axle rod extending upwards from an upper surface thereof and a block disposed on a lower surface thereof, the axle rod passing through the electric circuit plate and the core cover-plate, and then being firmly engaged with the core plate of the lock core body; and,
an actuating elastic assembly engaged in an inner wall of the housing and having a contact member and an elastic member, the contact member provided to be contacted with the electric circuit plate.